1. Technical Field
The disclosure relates to light emitting devices and, more particularly, to a light emitting diode (LED) unit.
2. Description of Related Art
LEDs (light emitting diodes), available since the early 1960's, have been increasingly used in a variety of application fields and are intended to be a high quality replacement for conventional light sources due to high light-emitting efficiency, environmental friendliness, and low power consumption.
Conventionally, light directly output from the LED does not have a desirable pattern; therefore, a light-adjusting element, such as a lens, is used with the LED to adjust the light pattern thereof. All of the light output from the LED must travel through the lens, which inevitably produces a loss of light intensity due to a light refraction or a light reflection or a combination thereof, occurring when the light radiates through the lens. Thus, an LED unit including an LED and a lens obtains a low light emitting efficiency.
What is needed, therefore, is an LED unit which can overcome the limitations described above.